How a Plastic Model of the Moon Was Made

Home , Abenezra (crater), Abulfeda (crater), Alhazen (crater), Anaximander (crater), Anaximenes (crater), Archytas (crater)

--a"1 ---ZFT ----'wo -sy-" --;- '0-; ms"crz ;v-ac' ""m7�- -'tnT�r-z wz'rs3a�zt� G 68 SCIENTIFIC AMERICAN SUPPLEMENT No. 2013 August 1, 1914

' The moon, 8 Yz days old, as seen First quarter, as seen on the Last quarter, as seen on the sculp The moon, 20 Yz days old, as seen through the telescope. sculptured moon. tured model. through the teles�ope.

The Hemisphere of the Moon Constructed After Telescopic Photographs

By Herbert Collier

AFTER some years of telescopic observation with a blurry confusion in the fierce light of overhead rays. In undertook the systematic photographing of the moon. A Brashear telescope I determined to undertake the task such a moving picture there is a peculiar fascination. unique telescope was designed, and elaborate plans and of sculpturing the moon, mainly for the, purpose of at A new panorama presents itself each night to the watch specifications made for this remarkable undertaking. taining greater familiarity personally with every detail ful eye. To see it all is impossible, as the moon is in The instrument was an ingenious combination of a huge of the surface. the visible sky for but a few hours comparatively, and object-glass or light collector nearly two feet in diam When you consider that the artist's model was some nightly vigils with the telescope are sure to be inter eter and mirrors. Equatorially mounted and�driven by 240,000 miles away and had gained a reputation rupted frequently by cloudy weather or bad atmos clockwork, the refracting lens faithfully followed the through the ages of being "fickle," some of the difficul pheric conditions. Thus a long course of looking is ob object across the sky, while the mirrors, two in num ties become apparent. Every day the moon has a dif ligatory before the student by personal observation ber, were so arranged as to convey the image thus se ferent appearance-a new dress every sitting. As the knows the surface of the moon thoroughly. cured through a tube in the wall to the eye-piece situ sunlight creeps over the hills and lights up the moun Though my eye had registered through the telescope ated within a comfortable room. Here the camera was taiu peaks, the view of yesterday changes, and quite a thousands of impressions of the surface markings of attached, and the 'men worked free from the usual new aspect results. New valleys, great yawning craters the moon, I dared not trust that organ solely in trans bodily discomforts associated with the ordinary tele jump into view with their dark depths untouched by ferring them to sculpture.' Accuracy of result de scope. even a glimmer of twilight, forming a background of manded exact measurements. Telescopic photographs While some of the finest individual photographs of Rembrandt's choosing. Continually the terminator, the present an unchanging recorq. They give an indelible the moon have been taken by the great telescope at the irregular dawn line dividing light and darkness, is impression of what is revea:�ed, and such permanent Yerkes Observatory, which is the largest refracting tele moving forward. On the earth this travels at the rate record is ready for investigation at all times. Beyond scope in the world, nothing can Compare with the series of about 1,000 miles an hour, completing the circuit of question, photography pr,e-emi'i.tently has enabled astron secured by the Paris astronomers through years of de the globe in one day:' On the moon this movement is omy to merit the title given ,it to-day "the most exact voted effort. Thousands of photographs were taken of about 225 miles per diy, or nearly 10 miles an hour, for of sciences." Therefore- I made, as the foundation of the moon at all stages of its progress from new to full, the earth turns round 29% times to one revolution of my work, the best series of photographs of the moon and then on to new again. Possibly twenty would be the moon. that the world has to-day, which is known as the Paris secured one night and but one selected as good enough The details of cr3{ters-breadth and depth, a crag Atlas. to enter the atlas. These pictures form a wonderful here, a precipice then�--show clearly, contrasted by the Twenty years ago M. Loewy, the gifted director of catalogue of the topography of the moon, presenting far shadows. But as thi sun rises all this passes into the Paris Observatory, with his colleague, M. Puiseux, more minute details of the surface of our own satellite

Full moon as seen in the telescopes. Full moon as it appears on the model,

1 Kastner 78 Bianchini NAMES CORRESPONDING TO KEY-MAP, LOCATING ALL PROMINENT OBJECTS ON THE MOON. 452 Burg 604 Epigenes 2 Maclaurin 79 Playfair 453 Plana 605 Fontenelli 3 Lapeyrouse 80 Fermat 220 Wargentin 256 Pictet 292 Purbach 416 Hahn 454 Posidonins 606 Anaximenes 4 Ansger 81 Pons 221 Weigel 257 Nasireddin 293 Lacaille 417 Berosus 455 ' Chacornac 607 Carpenter 5 Behaim 82 Azophi 222 Riist 258 Miller 294 Delaunay 418 Burckhardt 456 Romer 608 J. Herschel 6 Hecataus 83 Abenezra 223 Schiller 259 Sasserides 295 Thebit 419 Gauss 457 Macroibus 609 Anaximander 7 Philips 84 Donati 224 Bayer 260 Wilhelm I. 296 Right Wall 420 Geminus 458 Proclus 610 Pythagoras 8 Legendre 85 Faye 225 Schickard 261 Heinsius 297 Arzachel 421 Berzelius 459 Taruntius 611 South 9 Haze 86 Almanon 226 Inghirami 262 Hainzel 298 Alphonsus 422 Messala 460 Maskelyne 612 Harpalus 10 Furnerius 87 Catharina 227 Lehmann Bouvard 263 Lexell 299 ptolemaus 423 Franklin 461 Sabine 613 Xenophenes 11 Marinus 88 Cyrillus 228 Drebbel 264 Hell 300 Wm. Herschel 424 Cepheus 462 Ritter 614 Plato 12 Oken 89 Theophilus 229 265 Gauricus 301 Alpetragius 425 Oersted 463 Arago 615 Plato A. 13 Fraunhofer 90 Beaumont 230 Clausius 266 Wurzel bauer 302 Lassell 426 Volta 464 Sosigenes 6J6 Condamine 14 Brisbane 91 Madler 231 Lacroix 267 Pitatus 303 Davy 427 Long 465 Godin 617 Bouguer 15 Hannon 92 Torricelli 232 Piazzi 268 Hesiodus 304 Lalande 428 Mercurius 466 Rhaeticus 618 Straight Range 16 Pentecoulant 93 Hypatia 233 Lagrange 269 Cichus 305 Flammarion 429 Endymion 467 Tresnecker 619 Cape Laplace 17 Biela 94 Delambre 468 Agrippa 620 Cape Heraclides 18 Hagecius 95 Taylor Soul' H 469 Ukert 621 Bianchini 19 Helmholz 96 Kant 470 Hyginus 622 Sharp 20 Boussillgault 97 Descart�s . 471 Boscovich 623 Mairan 21 Boguslawsky 98 Abulfeda 624 Repsold 22 Manzinus 99 Hipparc'hus 625 Harding 23 Mutus 100 Albategnius 626 Gerard 24 Simpelius $27 Lavoisier 25 Curtius 628 Ulugh Beigh 26 Pentland 629 Lich ten berg 27 Zach 630 Otto Struve 28 Jacobi 631 Aristarchus 29 Lilius 632 Herodotus 30 Cuvier 633 Schiaparelli 31 Bacon 634 Seleucus 32 Pitiscus Kraft 33 Rosenberger 34 Vlacq 35 Steinheil 36 Janssen (S) 37 Fabricus 38 Metius

39 Rheita 40 Stevinus 636 Cardanus 41 Snellius 637 Galileo 42 Reichenbach 638 Marinus 43 Petavius 639 Reiner 44 Vendelinus 640 Olbers 45 Langrenus 641 Hevel 46 Webb 642 East 47 Messier ,643 Encke 48 Goclenius 101 Hind 475 Ross 644 Kepler 49 Guttenberg 102 Halley 476 Plinius 645 Kunowsky 50 Capella 103 Argelander 477 Jansen 646 Reinhold 51 Isidorus 104 Airy 478 Dawes '647 Copernicus 52 Colombo 105 Reaumur 479 Vitruvius 648 Gay-Lussac 53 Cook 106 Sacrobosco 480 Maraldi 649 Tobias Mayer 54 Santbech 107 Schamberger 481 Argaeus Mts. ,650 Euler 55 Bohnenberger 108 Janssen 482 Lemonnier 651 Diophantus 56 Fracastorius 109 Horrocks 234 Fourier 270 Capuanus 306 Masting 4:lO Atlas 483 Bessel 652 Delisle 57 Borda 110 Rothmann 235 Vieta 271 Ramsden 307 Birt 431 Hercules 484 Aratus 653 Gruithuisell 58 Neander 111 Lindenau 236 Palmieri 272 Vitello 308 Prom. Aenarium 432 De la Rue 485 Linne 654 Helicon 59 Picclomini 201 Newton 237 Cavendish 273 Mercator 3()9 Huggins 433 Strabo 486 Conon 655 Lavoisier 60 Stiborius 202 Moretus 238 Henry 274 Campanus 310 Liebig 434 Thales 487 Autolycus 656 Mt. Pico 61 Riccius 203 Cysatus 239 Byrgius 275 Kies 311 Lee 435 Democritus 488 Aristillus 657 Mt, Piton 62 Rabbi Levi 204 Casalus 240 Darwin 2'16 Doppelmayer 312 Hippalus 436 Kant 489 Theaetetus 658 Kirch 6:3 Zagut 205 Klaproth 241 Zupus 277 Mersenius 401 Schubert 437 Moigno 490 Cassini 659 Archimedes 64 Nicolai 206 Wilson 242 Fontana 278 Gassendi 402 Apollonius 438 Euctemon 491 Prot agoras 660 Timocharis 65 Biishing 207 Blancanus 243 Criiger 279 Letronne 403 Neper 439 Challis 492 Peirce 661 Lambert 66 Buch 208 Scheiner 244 Sirsalis 280 Billy 404 Firmin 440 Gioja 493. Eernouilli 662 Pytheas , 67 Maurolycus 209 Gruemberger 245 Trouvelot 2'81 Hansteen 405 Condorcet 441 Barrow 494" Timaeus 663 Eratosthenes 68 Barocius 210 Clavius 246 Rocca 282 Flamsteed 406 Auzout 442 W. C. Bond 495 Scoresby 664 Stadius 69 Licetus 211 Deluc 247 Grimaldi 283 Landsberg 407 Hansen 443 Ch. Mayer 496 Goldschmidt 665 Pallas 70 Stotler 212 Kircher 248 Damoiseau 284 Fra Mauro 408 Picard 444 Archytas 497 Meton 666 Schroter 71 Fernelius 213 Bettinus 249 Riccioli 285 Bonpland 409 Cape Agarum 445 Alpine Valley 498 Kirchhoff 667 S6mmering 72 Frisius 214 Bailly 250 Lohrmann 286 Pamy 410 Alhazen 446 Aristoteles 499 Schumacher 668 Gambart 73 Pont anus 215 Zuchius 251 Maginus 287 Guerike 411 Eimmart 447 Egede GOO Hooke 669 Briggs 74 AliacensiR 216 Segner 252 LongolllOntanl1S 288 L u biniezky 412 Oriani 44i1 EuejoxeR 1i0! ('",sar 670 Cava ]�l'inR 75 Walter 217 Yausen 253 Street 289 Bullialdus 413 Plutarch 449 Alexander 6()1 Anaxag01'3F1 ti71 Rainbow Bay 76 Werner 218 Procylides 254 Saussure 290 Agatharchides 414 Cleomedes 450 Calippus 602 Philolaus 672 Maupertius 77 Apian 219 Nasmytll 255 Tycho 291 Regiomontanus 415 Tralles 451 Baily 603 Birmingham 673 Foucault

© 1914 SCIENTIFIC AMERICAN, INC 70 SCIENTIFIC AMERICAN SUPPLEMENT No. 2013 August 1, 19 14 than we know of our earth in many regions. The atlas various conformations of the surface. They simply re 180 miles to the inch, a distance of 2 miles on the moon was to me a guide book superior to a personal visit. quire due conSideratiOn� would be 1/90th of an inch on the model. This is less Fearful lest through lack of knowledge of the tech The moon is a dead \':orld. The most minute inves than the thickness of your business card. A lunar nique of sculpture I should waste much valuable tigation indicates that nothing could be more so. A precipice of two miles height would be a very promi time, I devoted fully six months to the study of this dried up, wrinkled, wizened, scarred veteran, it bears nent object under proper lighting conditions, and be special feature. Then after consultation with a num the marks of terrible conflicts, of gigantic struggles. worthy of special attention. Yet an elevation of but ber of skillful artists I commenced operations. We know not its age. Did water once rush down those 1/90th of an inch on the model would be merely the Plasticine appeared best suited to the conditions wondrous mountain gorges? Did the sea ripple and thickness of a coat of paint! Therefore the elevations under which I was to labor. It is non-drying and re play about those towering capes Laplace and Heraclides were accentuated in order to produce to the eye a nat sponds quickly to manipulation with a tool. A sitting and at times dash madly against those great preci ural appearance, for the strict adherence to scale in of three or four hours, then a day or two, and another pices? We can only guess. Our fancy pictures, in the this respect would create misconceptions. Careful com sitting just as my spare time T)ermitied, Vrovcd plas distant past, smiling vegetation, life, joy, and happiness parison of photos of the real moon and the sculptured ticine an excellent medium for the purpose. in a world of glory. It is true there are some indica one, under approximately similar lighting, shows "How big shall I make it?" was a troublesome ques tions of this. But death came. Like a mummy it is marked contrast. But this was a feature that was not tion which received answer in the selection of a scale to-day. Life departed, embalmed, naught remains but in the least considered important. My aim was not to of 180 miles to the inch. The moon having a diameter the shrunken, desiccated, cracked carcass. The beauty attain photographic similarity, hut to convey to the eye of 2,160 miles, thus brought my work to a like meas of life is gone. Its history, its experiences written in under daylight conditions details apparent only on rare urement of 12 inches. This was a convenient workable the shroud, are in mysterious hieroglyphics, of which occasions with the telescope .. The scientific gave place basis and proved satisfactory in every respect. man has been able to decipher but little. To-day no to the artistic. For such departure I plead merciful Only half the moon is visible to us at any time, and, grass waves on the hillside. Not a single blade would consideration from my scientific friends. strange to say, it is always the same half. A presenta give the weary traveler a welcome. No bird warbles In the plaster casts made from the original, many of tion to "royalty" demands that madam turns not her his cheery song there. Not even the hated snake suns the finer details have been lost. As a light fall of snow back to the regal chair. The approach, the bow, and himself upon the many rocks. Not an insect flits about on rough ground spreads a brilliant blanket, While the retreat call for skillful manipulation of her trouble in quest of prey. Not a breath of air stirs. Not a sign leaving still the form of every stone and every hum some train, but she must keep her face ever to the of life appears anywhere. Inconceivable desolation! mock, so in the casting, the plaster obliterated the front. So the moon sedately cirCles about the earth, Night comes. The sun sinks behind the lofty hills, harshness of the model, softening all to a pleasing de and in true subservience observes this custom with re and suddenly all is dark. No twilight softly intervenes. gree. A realistic telescopic appearance resulted, which markable precision. Every 291h days the moon makes Cloudless the sky, devoid of air and moisture, no light in some respects compensated for the loss of details ob the circuit of the earth. At the same time she turns is reflected or refracted. There can be no diffusion. of tained only after much labor. By a careful applica completely round. Yet with provoking constancy does sunlight under such conditions. Black night sits side tion of a coat of paint of a bluish gray tint the maria, she keep that one side to us. A slight swaying of the by side with brilliant day wherever the rays of the sun or seas, were given a sufficient contrast from the snow ball called "libration" permits a peep at times of a are· intercepted. Behind the jutting rock, beneath the white plaster mountains to form in all an ideal full little more of the "edges" than the exact half, which ledge, within the cavern of broad entrance, it is night, moon:\ ' the ' le though day reigns supreme with intense brightness all A vrA'y interesting question appeared while calculat really makes a total of about 59 per cent of � . surface presented at different times to the earth. fon about. ing measurements, "What is the smallest possible dis sequently, half a sphere is really all we need to repre It is quite a surprise to many to learn that the' earth cernible object on the moon? Could you see a man sent the details of surface characteristics of the earth's presents more light to the moon than it receives in re there? Would a big tree show?" The average human satellite, which are known to mankind. 'l'herefore, as turn. Assuming that they possess the same reflective eye is credited with a power of appreciating an angle a foundation for my model I constructed a hemisphere power, the surfaces compare as 27 to 2. Thus the earth of about half a minute of arc. This, however, is quite of seleCted well-dried wood, laminated to prevent warp should be credited with reflecting more tJ.lan thirteen unintelligible to most people. Let us simplify it. It ing. The entire surface was then liberally treated with times as much light as its satellite. This light thrown moans that you should see an object one inch in diam shellac. With a diameter of 11 inches this wood Core upon the moon is known as "earthlight," and is in all eter at a distance of about five hundred and fifty-five allowed a blanket covering of plasticine 1h inch in thick respects similar to our moonlight. When the moon be feet. This would indicate that a "beauty plaster" of ness, thus giving a total diameter of 12 inches. A board gins its monthly journey around the earth by passing one-eighth-inch diameter upon the fair cheek of the 16 by 24 inches served as the base, and to this was -fas between the sun and us, the earth is "full moon" to it, debntantc should be visible at some sixty-nine feet. Ap tened the hemisphere of wood and plasticine. The while that body presents the phase of "new moon" to us. plied to the moon, which averages in size thirty minutes preparations were complete. Noting the date, May 1st, Thus the greatest amount of "earthlight" reaches the of arc, the unaided eye is capable of discerning a spot 1913, actual ope·rations commenced. It was eight dark portions of the moon at this time. It is this phe measuring one sixtieth of her diameter, or 30 seconds. months later when the finishing touches were applied. nomenon which gives rise to that beautiful sight, "the Now a linear mile on the moon corresponds to 0.87 of a The photograph of a ball such as the moon presents old moon in the young moon's arms." As the age of the second. Therefore a region one mile square must be mag some peculiarities. Take a 12-inch photo of a 12-inch moon increases, this reflected light from the earth grad nified by artificial means to equal 30 seconds, that the ball. Superimpose the apparent centers, at the same ually lessens until .there is none at full moon. Then as eye Illay even perceive it as a point. The power required time wrapping the photo paper around the faCe of the the moon nears the completion of its circuit the "earth is evidently about thirty-four. Measurements show that hemisphere. It is immediately apparent that they do light" continues to increase in proportion. a second of arc represents about two thousand yards not correspond and will not fit. The photo paper lacks While the moon is making this Circuit of the earth on the moon. Thus we would have to magnify an ob practically seven inches of covering its prototype. The 291h of our days pass by. Yet she takes all this time ject of that size thirty times to bring it to discernible reason for this is quite evident. If the photo is kept to have but one day and one night. Day brings heat proportions. Two hundred yards would require ten flat and vertical lines projected to the surface of the unbearable in its intensity. Scorching as the flames times this power, or 300. Consequently 20 yards would ball, they coincide perfectly. This tersely explains the from the inferno, the sun pours his streams of fire hour demand a magnifying power of 3,000! There must be method I adopted on account of its simplicity in trans after hour until the rocks fairly dance with molecular a very fine atmosphere to admit of the use of a power posing scale calculations. agitation. ]'01' fourteen days without a moment's re of 500. One thousand power is quite the limit. Even A photo of the full moon is very much like the pre lief this continues. Then with startling suddenness this latter magnification would bring the moon to a liminary sketch of the landscape painter. The seas, night appears. A temperature more than 200 degrees distance of 240 miles, and no object under Sixty yards those great dark regions which even the naked eye dis below zero assails all Without the kindly protection could possibly be detected, if our theory is sound. It cerns plainly, are nicely outlined. Some of the more of a cloud, stark naxed as it were, and thrust into a is quite evident that a man could not -be seen. A big prominent craters are noted. The more important temperature of glacial cold from such a bed of warmth, tree would not show. Aided by the most powerful tele mountain ranges are roughly indicated. But the details the results must be disastrous. Such .extremes of heat scope, and under -conditions of magnification verging of all these are to be shown later. I first selected such and cold as these cannot but result in anything less upon impracticability, it would be doubtful if an object a picture, an excellent. one from the 5-inch Brashear than gigantic destruction. Great yawning chasms ap less than one hundred yards in diameter would be dis telescope of D. B. Marsh, Sc.D., F.R.A.S. Being just 12 pear everywhere on the moon, some of which extend for cernible to the human eye as anything but Ii mere speck. inches in diameter, it served the purpose admirably of hundreds of miles. Close scrutiny of these numerous With but one hundred miles separating you from a an outline sketch or key. Various points on this were cracks, a thousand of which have been charted, sug mountain and with ideal atmospheric conditions, judge chosen and soon projected onto the model. As the gests to the observer the possibility of some slight extra what little your naked eye could determine of the work progressed craters and prominent physical fea disturbance resulting in a general disintegration of the details. tures, visible only in other photos, were first given their whole satellite. proper locations on this key, that they might thereby Seismic cOIlvnlsions appear to have taken place at be accurately placed on the model. certain centers in the early history of the moon, pro Melting Points in Commercial Brasses and J'Jach Paris photo gave in great detail one small dUCing remarkable results. The exterior of the molten Bronzes region. Possibly but one or two craters of importance mass had cooled sufficiently to form a crust, a brittle As the result of tests made under the direction of the would be shown. Another picture of the same region, glass-like covering. A large nUI)lber of the so-called T'nited States Bureau of Mines, the following table of but under different lighting conditions, would change craters had formed. Then with further cooling of the the melting-points of commercial brasses and bronzes the apparent physical features to a remarkable degree. molten interior tremendous expulsive force was exerted, has been summari�ed: Thus a number of pictures of eve.ry district, showing bursting the outer shell and throwing out great radiat the changes produced by sunlight coming from the east ing cracks in all directions, like spokes in a wheel. Approximate Composition. Melting-point. or from the west, must be carefully compared in order Lava then oozed up through these openings, in some Alloy. Copper. Zinc. Tin. Lead. C. deg. F. deg. to arrive at a full understanding of the real topography. cases but partly filling them, in others overflowing. Gun-metal ...... 88 2 10 995 1825 With a hundred such photos before me constantly, this Congealing and solidifying under different conditions Leaded gun-metal. ... 85% 2 911.. 3 980 1795 Red brass ...... 85 5 5 5 970 1780 task was by far the greatest and of prime importance. from the remaining crust, this formation is quite dis Low-grade red brass 82 10 3 5 980 1795 There are no twilight shadows on the moon. A glance tinctive in appearance, showing as bright streaks. The Leaded bronze ...... 80 10 10 945 1735 at a dark spot may lead to the conClusion that a great crater Tycho at the south pole is the center of the Bronze with zinc .. . 85 5 10 980 1795 hole is there, to which the sunlight has not as yet been greatest system of these light streaks, and thus was at Half-yellow, half':red 75 20 2 3 920 1690 Cast yellow brass .. . 67 31 2 895 1645 Hdmitted. Further investigation of it in other pictures one time in the throes of a seismic disturbance of Ull Naval brass ...... : . 61% 37 1',1, 855 1570 reveals the fact that there is no such cavity, and that paralleled magnitude. Some of the streaks from this Manganese bronze .. 870 1600 the slmdow is due to the pp('ulinr conformation of an c('nter appear to encircle almost half the moon, thereby inten'ening hill. Though the sbadows thus appear ilflicating the violence attendant upon this great shock. The melting-point given is the "liquidus," or point puzzling and are sometimes very mislcafling, they are Vn order to give to the eye the effect attained by tele- where the alloy is completely molten. The tests are quite necessary for an understanding of the height of a scopic observation, I took the liberties of the artist and described in detail in Technical Paper No. 60.-Ameri crater wall, and a hundred other measurements of the departed from scale measurements in one respect. With can Machinist.